Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean: Vol. 4, Pt. 3

BOTANY.
SISYMBRIUM OFFIcINALE, Scop.; Torr. & Gray, Fl. 1, p. 91. Near Benicia, April 24. Doubt
less introduced.
SISYMBRIUM CANESCENS, Ntt. Gen. 2, p. 68; Torr. & Gray, Fl. 1. p. 92. Var. CALIroarIauM,
Torr. & Gray, 1. c. Williams' River of the Colorado, New Mexico. February 6-18.
SISYMBRIUM DEFLEXUM, (Harvey, Mss. in herb. Gray:) annuum, pilis patentibus hispidulum;
caule stricto, folioso simplici, foliis oblongis inferioribus pinnatifidis sen pinnatipartitis, segmentis
lineari-lanceolatis distantibus laciniato-dentatis integrisve, sinubus obtusis; foliis supreme linea ribus integris; pedicellis brevibus cum siliquiis angustissimis rectis elongatis teretiusculis arcte
deflexis. Turritis? lasiophylla, Hook. & Arn. Bot. Beechey, p. 321? Hill-sides, Napa valley,
April 26. About three feet high, slender, the lower half almost hispid, with short spreading
hairs. Lower leaves petiolate, 2-3 inches long, more hispid than the stem; middle leaves
sharply toothed; the highest 2-3 lines wide, and usually entire. Flowers about as large as in
Cardamine hirsuta, and apparently white. Petals oblong-spatulate. P6ds 2-3 inches long,
and scarcely half a line wide. Pedicles 2 lines long. Cotyledons incumbent. This plant re sembles a Sisymbrium from Coulter's Californian collection, sent to us by Dr. Harvey under
the name of S. deflexum -Harv., of which we believe no description has yet appeared. A
smoother and more humble form of it (some of the specimens only 2 or 3 inches high) was
collected near San Francisco, April 3.
SISYMBRIUM INCISUM, Engelrm. in P1. Fendl., p. 8. Mountain arroyas, near San Antonita, New
Mexico; October.
ERYSIMUM ASPERUM, DC. Laguna Blanca to the Sandia mountains.
TIELYPODIUM WRIGIITrII, Gray, P1. Wright. 1, p. 7. Rocky places on the Pecos; September.
Many of the flowers are in an enlarged and abnormal state, probably from the stinging of insects.
TROPIDOcARPUM GRACLLE, Hook. Ic. 1, t. 43; Torr. & Gray, Fl. 1, p. 94. T. scabriusculum,
lH6ok. 1. c.; Torr. & Gray, 1. c. Plains near San Gabriel, March 23. We find the two species
of Hooker to pass into each other.
ERYSIMUM ASPERUM, DC. Syst. 2, p. 506; Torr. & Gray, Fl. 1, p. 94 Near San Francisco,
April 3, and mouth of Santa Rosa creek, May 1, (with flowers and immature fruit.) Flowers
cream-color or pale yellow, becoming deeper in drying. A variety (or possibly distinct species)
with much larger and orange-yellow flowers, was found at Cocomungo, March 17, without
fruit; also found by Mr. Wallace. We are unable to find characters that will clearly distinguish E. Arkansanum and E. elatum from this species. The leaves and degree of pubescence
are very variable, and the pods seem to be the same in all of them.
VESICARIA ARGYREA, Gray, P1. Lindheim. 2, p. 147. Arroyas and canons, Williams' River
of the Colorado, New Mexico, February 7-26.
VESICARIA FENDLERI, Gray, P1. Fendl., p. 9. Bluff, and rocky places, New Mexico; October.
To this very polymorphus species must be referred V. stenophylla, Gray, P1. Linds. 2, p. 149.
DRABA AUREA, Vahl; Hook. Bot. Mag. t. 2934. San Antonita, New Mexico, and in the
Sandia mountains, in rocky places; October. Mostly in fruit. From these specimens the
plant appears to have a biennial root, while those of Fendler would seem to be perennial. The
silicles are mostly twisted.
DRABA CUNMrFOLMA, Nutt. in Torr. & Gray, Fl. 1, p. 108. Williams' River of the Colorado;
February 11.
DITRYREA WISLIZENI, Engelm. in Wisl. 2e1m. New Mex., p. 11; Torr. in Marcy, Expl. Recd
River, t. 11. On prairies and sandy bottoms of the Canadian, near Antelope Hills; September. It is from this region doubtless that the plant was first collected by Dr. James.
DITHYREA CALIFORNIcA, Hiarv. in H]ook. Lond. Jour. Bolh. 4, p.77a, 1. 5; ZEngeim. in Wisliz. Mexc.
p. 95. Sandy hills on the Colorado of the West. February 22. The radical leaves are deeply
lyrate-pinnatifid. The calyx is 4 or 5 lines long; much longer, narrower, and more closed
than that of D. Wislizeni. The petals appear to have been purple.
LEPrDIUM NITIDnM, Nutt. in Torr. & Gray, Fl. 1, p. 116. Sandy plains, Cocomungo; March
66